Comment 8 for bug 1428121
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| Kelvin Middleton (kelvin-middleton) wrote | #8 |
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67d34a1
(Get the code!)
Glad to see this bug report isn't completely dead.
Can confirm too that the problem still exists with kernel 4.2.0-27-generic with the same motherboard as per the original bug report.
The attached is a recent extract from dmesg outputs...I use vfio passthrough for GFX on a Windows guest. You can see from the timestamps that I start the guest at 21:02:44 and at around 21:26:07 I get some DMAR faults pertain to device at 00:02.0. This device is the Intel IGD...
lspci -s 00:02.0
00:02.0 VGA compatible controller: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller (rev 06)
...not sure if this is related to the HDMI audio or not.
What I can say is that I have to boot the host with "intel_iommu=on". If I change this to =on,igfx_off then my syslog fills with constant complaints about DMAR for another device I use in passthrough which works perfectly with =on, this device is a DVB-S2 device. If I use =igfx_off this stops IOMMU so I can not longer passthrough PCI devices but presto the HDMI audio now works?!